Has anyone tried running 6-cyl DIS with the 7749 ECM?

[Darth Fiero]

I was wondering if anyone has tried hooking a sy/ty ecm up to DIS. I would like to know because I am thinking of converting a friend's GN Turbo MAF system over to the faster speed-density based sy/ty computer using a 3-bar MAP sensor. Thanks for the info in advance.

 

[TurboTony]

I'm working on this as well. Same idea as you.

I "think" it will work, just have to give the ecm the correct timing offset to match the physical trigger point on the buick module.

Of course the injectors will fire bank/bank instead of sequential, but thats okay.

If this works on the buick the next step is to adapt it to a syty, wouldn't that be nice


Tony

 

[Darth Fiero]

I am not sure any timing offset would be needed to make the DIS work with the Sy/Ty ECM. I am pretty sure that the ignition module has sole control over coil dwell time and just waits for the ECM to "trigger" coil firing. If one is wishing to put DIS on a Sy/Ty, it would be fairly easy to use the coil pack and module from a Chevy 2.8/3.1/3.4L 60 degree V6 engine. If I am not mistaken, the module just looks for either a 3x or 6x analog signal with an offset No. 1 4th or 7th notch to let the module know TDC sync. This could be accomplished by either machineing notches in the balancer and mounting a PM sensor to one of the serpentine brackets at the right air-gap or use the plastic timing cover from a V8 vortec engine and machine the proper reluctor ring similar to the vortec V6. The crankshaft position sensor from the Vortec may not work because it is the 3-wire, "active" type requiring input voltage from the module to function to put out a digital signal. The 60 degree V6 coil pack module uses a permanent magnet, 2-wire "passive" sensor that supplies its own voltage analog signal to the module.

 

[smeagol]

When/if I do this, I'll be using the FAST Edist and LS1 coils. All you need to fab is some sort of cam sensor on the existing distributor. The LS1 coils are superior to any sort of waste spark setup; they are easy to get find cheap now too. No need to do any sort of crank pulley modification. The extra $ spent on the Edist is worth it to me, just to use the LS1 coils.

Gordon Jennings in California has a DIS / waste spark setup running on his Ty, but had problems with it last I heard. He's a sharp guy, so you guys need to get in touch with him to see what he's done, as he was doing exactly what you have described. Might save you some time.

 

[Darth Fiero]

The newer Vortec V6 4.3L engines already have a cam sensor in the distributor. You could just run one of those plastic distibutors as a dummy and then see if you could use it's existing hall-effect cam sensor output. Just an idea.

 

[smeagol]

Yup I have one of the L35 distributors here, just don't have one of the LF6 distributors. I believe the regular tach signal is different though.

 

[Darth Fiero]

I believe the LS1 style coils and modules do not have the ability to interperate the CKP/CMP signals directly, the LS1 PCM controls coil triggering directly wereas each coil-mounted module controls charge and dwell time.

I am not familiar with aftermarket computer systems so I am not sure what they will and will not work with. I can tell you that the Buick DIS module like those from the 3.0/3.3/3.8 engines work on a hall-effect system which may be directly compatible with the type of signal supplied by the Vortec's CKP/CMP signals although you will need to change the reluctors.

But as you said, you are running 1-coil per cyl so using the Buick DIS module is out of the question.

 

[smeagol]

FAST's eDist is the module that will control the LS1 coils... a bit spendy, at $300 ish I believe... but this setup has worked for sure in other vehicles. I know of a Supra running a FAST ecm with FAST's eDIst and LS1 coils.

 

[Darth Fiero]

FAST's eDist is the module that will control the LS1 coils... a bit spendy, at $300 ish I believe... but this setup has worked for sure in other vehicles. I know of a Supra running a FAST ecm with FAST's eDIst and LS1 coils.

Will the eDist module work with a stock GM ECM to control LS1 ignition coils on like a TPI engine if I run the appropriate CKP and CMP sensors?

 

[smeagol]

Yep, that's the whole point of it.

Provide your ECM with the stock crank signal, the EST line out to the coil now goes to the eDist, along with a cam sensor.

So you have to add some sort of cam sensor, do the wiring, and yer done.

LT1 guys have already run the LS1 coils this way, I know of a Buick guy running LS1 coils on his GN also. The Buick guy noticed a huge seat of the pants difference FWIW.

 

[PCS74]

We have done alot of cars with the ls1 coil setup. Porsche's, Mitsubishi's, Honda's, Toyota's etc.

Many of the cars we have run them on experience ignition problems when we reach ~180hp/cyl or greater(which in most of the cars has correlated to the mid 30psi range or greater). Better power supply, tighter gaps, better wires etc. did not show improvement. In every instance where we have experienced ignition problems with them, switching to Msd pro power hvc coils has eliminated the problem.

The ls1 coils do operate better when they are run with 2 ground wires rather than a 0v and ground, but we just started doing this so we don't have enough info yet to say that it will eliminate all ignition problems we have encountered.

Other cars run fine with the ls1 coils at any power level.

Production quality evidently varies quite a bit.

The Msd pro power hvc are too large and heavy for dis use in most applications. We haven't tried their dis racing coils yet, but we have a set waiting. We expect better operation from them than the ls1, but won't know for sure until mid next summer.

For ls1 coils we have found the best engagement with Ferrari f355 boots and terminals. MSD now has ls1 specific terminals, but the Ferrari are much better.

HTH,


Chris Skarzenski

 

[canadian]

mo' info:

http://www.diy-efi.org/diy_efi/archive/2001-December/msg00892.html -> DIS on a GN.

 

[UNIsackV6]

We have done alot of cars with the ls1 coil setup. Porsche's, Mitsubishi's, Honda's, Toyota's etc.

Many of the cars we have run them on experience ignition problems when we reach ~180hp/cyl or greater(which in most of the cars has correlated to the mid 30psi range or greater). Better power supply, tighter gaps, better wires etc. did not show improvement. In every instance where we have experienced ignition problems with them, switching to Msd pro power hvc coils has eliminated the problem.

The ls1 coils do operate better when they are run with 2 ground wires rather than a 0v and ground, but we just started doing this so we don't have enough info yet to say that it will eliminate all ignition problems we have encountered.

Other cars run fine with the ls1 coils at any power level.

Production quality evidently varies quite a bit.

The Msd pro power hvc are too large and heavy for dis use in most applications. We haven't tried their dis racing coils yet, but we have a set waiting. We expect better operation from them than the ls1, but won't know for sure until mid next summer.

For ls1 coils we have found the best engagement with Ferrari f355 boots and terminals. MSD now has ls1 specific terminals, but the Ferrari are much better.

HTH,


Chris Skarzenski

This is good to know thanks for the information. Have you tried running e-Dist on an Oddfire motor? I know its a shot in the dark but....it doesn't look like the FAST e-Dist will accept odd ignition pulses but we are going to try again. Ryan

 

[TurboTony]

I've been reading/thinking more about this. Here's my thoughts.

Use a buick dis setup, possibly the type two, with 3 seperate coils as opposed to the maganvox setup.

Then we could use the vortec hall effect sensors, crank and cam.
Should be a bolt on type deal. Timing cover, crank sensor, reluctor, cam sensor/dist assembly.

Now here are the problems that will have to be worked out...

The GN module uses the inputs by powering the GN style sensors with 10 volts from the module itself.
The vortec system powers the sensors with a fused 12 v source, will they operate at 10 volts? Dunno, will just have to try it i guess

Will the syty code support DIS? well I know of one guy that did it without any code changes, but he used a 2.8 3.1 DIS setup.
All he had to do was correct the tdc offset to line up the actual tdc with the sensor tdc. That should be a matter of a bit of time with a degree wheel.

At this point I haven't actually mocked anything up, just read up and trying to sort out what I'm dealing with. I may just scrap the whole idea and go with an MSD billet distributor.


Tony

 

[PCS74]

This is good to know thanks for the information. Have you tried running e-Dist on an Oddfire motor? I know its a shot in the dark but....it doesn't look like the FAST e-Dist will accept odd ignition pulses but we are going to try again. Ryan

No, I have no experience with the edist at all. I've been wanting to have a go with one just to see how it works out and what it's all about, but we rarely see fast products. Sorry I couldn't help.

Chris S

 

[UNIsackV6]

This is good to know thanks for the information. Have you tried running e-Dist on an Oddfire motor? I know its a shot in the dark but....it doesn't look like the FAST e-Dist will accept odd ignition pulses but we are going to try again. Ryan

No, I have no experience with the edist at all. I've been wanting to have a go with one just to see how it works out and what it's all about, but we rarely see fast products. Sorry I couldn't help.
Chris S

No problem, thanks for the response...Ryan

 

[tyndago]

Skylines - Coil on plug setup....

Running big power - nitrous /boost....

We have had luck with the B & M New Volt to pump up the voltage to the coils...